Poznań, located in the valley of the Warta (German Warthegau) in Poland. Originally part of the Kingdom of Poland, Poznan was formerly known as Posen, a Prussian province from 1848 to 1918. At the end of World War I most of the province was handed over to Poland and it became known as the Poznań Voivodeship from 1921 to 1939.

During World War II it was occupied by Nazi Germany and annexed as Reichsgau Posen, later known as Reichsgau Wartheland or Warthegau. Hundreds of thousands of Poles were expelled from the area. It was here that Mennon­ites from Galicia and Russia found temporary asylum during World War II, being settled on lands pro­vided by the German government.

In January 1945 Soviet troops overran the area and many Mennonites who had sought refuge in the area were returned to the Soviet Union. At the end of the war the Warthegau again became the Poznań Voivodeship. The borders of the province were redefined in 1975 and in 1988 it was superseded by Wielkopolska (Greater Poland) Voivodeship.